<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>固定定位</title>
		<style>
			.ad1,.ad2{
				width: 100px;
				height: 200px;
				background-color: black;
				color: white;
			}
			.ad1{
				position: fixed;
				top: 100px;
				left: 0;
			}
			.ad2{
				position: fixed;
				top: 100px;
				right: 0;
			}
		</style>
	</head>
	<body>
		<div class="ad1">我是广告</div>
		<div class="ad2">我是推广</div>
	</body>
</html>
